Fountain pen

ABSTRACT

A fountain pen, in which the barrel of the pen includes an ink holding body in the form of a coiled up strip having webs on one face to hold the convolutions of the coiled up strip apart to create capillary passages. Ink can be supplied to the body from the pen end thereof or from the opposite end thereof. The body is held in the barrel of the pen between ink conducting bodies which interconnect the capillary spaces in the body and one of which communicates with the pen to supply ink thereto.

United States Patent [1 1 Herrnring FOUNTAIN PEN 1 Apr. 3, 1973 2,847,976 8/1958 Spaulding ..401/223 x 2,684,052 7 1954 Rickmeyer ..401 134 2,587,949 3/1952 Zodtner ..401 223 2,782,763 2 1957 Zodtner ..401 223 2,784,699 3 1957 Schaeffer 401 223 2,855,898 10 1958 Dyson 01/223 x Primary Examiner-Lawrence Charles Attorney-Walter Becker [57] ABSTRACT A fountain pen, in which the barrel of the pen includes an ink holding body in the form of a coiled up strip having webs on one face to hold the convolutions of the coiled up strip apart to create capillary passages. Ink can be supplied to the body from the pen end thereof or from the opposite end thereof. The body is held in the barrel of the pen between ink conducting bodies which interconnect the capillary spaces in the body and one of which communicates with the pen to supply ink thereto.

22 Claims, 14 Drawing Figures FOUNTAIN PEN .stantially'constant.

Heretofore known fountain pens of the above mentioned type have the drawback that the ink stored therein is released only incompletely and in most instances irregularly. A particular difficulty is encountered when producing fountain pens of the above described type, particularly with regard to establishing the connection of the capillary storage means with the writing element in a simple and safe manner.

The term fountain pen as it is used in this application, in addition to comprising a complete writing instruinent, also includes a writing insert which similar to the cartridge of a ballpoint pen can be inserted in a corresponding housing and can be discarded when it is exhausted.

It is an object of the presentinvention to provide a fountain pen which will overcome the above mentioned drawbacks.

It is another object of this invention to provide a fountain pen, especially for fast flowing inks, while the fountain pen can be produced with a minimum of parts and at low costs.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 is anaxial section through the front end of a fountain pen according to the invention. I

FIG. 2 illustrates in a broken-off side view andon an enlarged scale the tube which carries the helical body.

FIGS. 3-5 represent cross-sections taken along the lines- III III, IV IV and V Vrespectively of FIG.

' I IG. 6 is a'topview of the ink conducting bodywhich closes the helical body off from below. I FIG. 7 is a vertical section along theiline VII VII of no.1. I

FIG." 8 is a top viewof a section of 'thehelical paths for the tubular helical body on -a greatly increased scale.

FIG. 9 represents a section taken along the line IX IX of FIG. 8.

FIG. 10 is an illustration-similar to that of FIG. 8 and shows a'modified design of thehelical paths of the. helical body.

FIG. 1 1 represents a diagrammatic illustration-to show the distribution of thewebs overthe length of the helical paths of-the helical body.

FIG. 12 is a broken off vertical sectionthrough the front closing member'of the fountainpen accordingto the invention.

FIG. 13. is a cross-section taken along XIII, on the scale of FIG. 12, of FIG. 1.

FIG. 14 is a top view of the unfinished correspondingly curved pen illustrated in section, in FIG.

The fountain pen according to the present invention in which for purposes of storing ink there is employed a helical tubular body the spiral-shaped capillary storage the line XIII means of which is formed by superimposed helical sections with webs therebetween while the height of the webs is substantially constant, is characterized primarily in that the helical tubular body has in axial and radial direction a capillarity which increases toward the pen. In this connection it is of particular advantage so to design the spacing between the webs in the layers of the helical body that the spacing increases with increasing diameter of the helical body and further decreasing in axial direction toward the pen. The distance between the webs may advantageously be so dimensioned that the webs of adjacent helical layers are offset with regard to each other.

The present invention is further characterized by the feature that the end face of the helical body at the side of the pen isdrawn inwardly in a substantially truncated cone-shaped manner and engages an ink conducting body which with regard to the end face of the helical body forms air passages and ink capillaries which interconnect the indidual helical layers. For purposes of aligning and securing the layers of the helical body, ofthe ink conducting body, it is suggested according to a further feature of the invention to employ a tubular member which within the region of the end faces of the helical body is perforated by ventilating windows and which outside the helical body has axial folds which positively cooperate with the ink conducting bodies.

Referring now to the drawings in detail, the fountain pen illustrated FIG. 1 comprises in customary manner ,a mantle tube 1. The writing pen 20 protrudes from the lower end of the tube 1 and surrounds the ink storage means 30 and also surrounds the ink conducting means with the pen.

The article shown in FIG. 1 may represent a fountain pen insert or a cartridge which is insertable into a special housing as it is known in connection with fillers or refills for ballpoint pens. In order when so using the article of FIG. 1, to prevent the insert from rotating, the mantle l, as indicated in FIG. 1 by dash lines, may be provided with camsor guiding ribs 9 which will prevent a rotation and therebysecure the position of the insert.

The front end of the mantle tube 1 is closed by aperforated closure member 3 whereas the rear end of tube 1 is closed by a perforated closure member 2. A

preferably two-part tubular body 40 extends between the closure members 2 and 3 and has its central smooth-walled portion forming the core for the helical body 30. The lower and upper closure members of the 1 5. The rear end of the upper closure member 2 is providedwith a recess 4 for an ink cartridge 6 which can I be connected to the seat area 5 in a liquid-tight manner in order, after exhaust of the ink storage means, to refill ,the same formed by the helical body 30, through bore 7. To this end, the rear end of the closure member 2 may be provided with a push-open element known per se.

I There will now be described the individual elements of the fountain pen construction shown in FIG. 1.

FIG. 2 shows one portion of the tubular body 40 illustratedin FIG. 1. This section comprises a smooth walled part 42 and an end portion 41 provided with axial folds or ribs 46. The smooth walled portion 42 serves as winding core proper for the helical body 30, whereas the tubular part 41 with the axial folds 46 serve for securing the position and the connection in the closure members 2 and 3 and also for holding the ink conductors 50 and 50'. At the area where the folds 46 merge with the smooth surface of part 42, the folds are machined off over a length of approximately millimeters whereby in the surface of the tube 40, windows 43 are formed forming ventilating and filling openings.

As shown in FIGS. 6 and 7, the ink conductor 50 and also the ink conductor 50' which for manufacturing reasons is designed the same way as the ink conductor 50, has a central bore 55 which corresponds to the outer diameter of the smooth walled tube portion 42. This bore 55 is at the bottom thereof provided with widened portions 54 into which the ends of the folds 46 at the merging area of the two tube portions 41 and 42 may positively extend. The dimensioning is effected in such a way that the just mentioned windows 43 extend into the region of the adjacent end surfaces of the helical body 30. As will be evident from a comparison with FIG. 1 the outside air can through bore 8 of the closure member 3 and through bore 44 of pipe 40 reach the end face of the helical body 30 through the windows 43. For purposes of providing the end face of the helical body 30 with air on all sides, the ink conductor 50 has three radial slots 53 which with each other form right angles. In the free range between the two air slots 53 which are located opposite to each other, the conical surface of the ink conductor has a large surface flat recess which together with the adjacent end face of the helical body forms a capillary ink gap 52 which preferably in the direction toward the pen becomes narrower which means in this direction has a greater capillarity. This wedge-shaped gap aids the discharge of air bubbles in the direction to the window 43 of the tube 40.

As will be seen from FIGS. 1 and 13, the lower ink conductor 50 also serves for holding and guiding the writing pen which latter is designed as shown in FIG. 14. Over an arc of approximately 180, the ink conductor 50 is slightly machined off so that with regard to the tube 1, a narrow gap is formed which corresponds to the thickness of pen 20. Ears 23 provided on the pen 20 rest against the ink conductor 50 and with angled portions 23 engage the air slots 53 of the ink conductor 50.

The capillaries 21 which are covered up and lead into a pen gap 22 are at the upper end of pen 20 opened by a machined-off portion and in this area are adjacent the capillary ink gap 52. Air slots 25 at the upper end of pen 20 serve for ventilating the annular space which is provided within the tube 1 and surrounds the helical body 30.

FIGS. 8-10 illustrate the widened helical path 31 of the helical body on a highly enlarged scale. From a smooth or slightly roughened foil path, solid parallelepiped-shaped cams or webs 32 protrude. The foil path 31 and the webs 32 may consist of different materials firmly connected to each other while the materials and their connection are ink resistant and must be flexible and may consist for instance of synthetic materials such as polyesters, polyethylene,

ABS, photoresistance, screen printing dyes or metals as for instance aluminum, copper, etc. The webs 32 are arranged in rows 35 and are interrupted by gaps 36. The webs 32 between the individual rows 35 are offset with regard to each other so that the ink film flowing therebetween will in case of an axial shock be held better as if by impact walls. The individual rows of webs 35 together with the next following smooth side of the helical path 31 form gaps in the helical body 30, the cross section of said gaps being determined by the distance 38 between the rows. As shown in FIG. 10, the foil path 31 may have holes 37 which in wound-up condition interconnect the individual helical layers. The webs 32 may for instance have a width of from 0.1 to 0.2 millimeters and may have a length of l millimeter while they may have a height of 40 microns. The distances 36 approximately equal the distances 38 between the rows.

The course of the rows of webs 35 on the entire stretched out helical path 31 of the helical body 30 is indicated in FIG. 11. For reasons of a clear description of the rhombus-shaped cut of the helical path which cut follows from the truncated cone-shaped ends of the helical body 30, is not illustrated. The shorter rhombus side is the start 39 of the helical body 30 on the central helical tubular body 30 which rests on the central tubular body 40. The end 39 of the helical path 31 of the helical body 30 is the wider side of the trapezoid and after the winding-up operation is connected for instance by adhesive means or an adhesive strip. The numbers a1-a58 at the margin of the helical path 31 designate the number of helical or winding layers starting with the innermost layer of that side of the helical path 31 which faces away from the pen. At the margin of the helical or winding path 31, which is at the side of the pen, the number of the winding layers are designated with blb66. The course of the web row 35 in the individual layers is indicated by the dash-lined pairs of lines between the margin which faces toward the pen and which faces away from the pen. Each pair illustrates the course of a web row 35 and of the tenth following web row 35. As shown in FIG. 11, the distance 36 between the web rows 35 is the shortest in the innermost winding layer and increases with increasing diameter of the helical body 30. Furthermore, FIG. 11 shows that the distance 38 of the web row 35 from the margin of the winding path 31 facing away from the pen widens toward the margin which faces toward the pen. Inasmuch as the distance 38 of the webs 32 at the margin (bl-b66) at the side of the pen is-greater than at the margin (al-a58) remote from the pen, the angle a between the angular path margin (bl-I266) at the side of the pen and the web row 35 becomes less with increasing number of the windings from b1 to b66. When winding the helical web 31 .into the helical body 30 about the helical pipe body 40, the individual webs 32 will in adjacent windings not be located upon each other in such a way as to cover each other. With the same web height, in view of the widened distance 38 of the webs 32 with an approximately cylindrical path of the helical webs 31 in the helical body 30, the medium gap height decreases by the height of the arrow of the circular section. A similar decrease occurs when with a polygon, the webs 32 of the successive helical webs are ofiset with regard to each other. For the distance 38 of the webs 32, assuming an approximate cylindrical surface there may be formulated the following formula:

V l .f1(

In this formula, R represents the variable radius of the helical body 30 and the K factors are constants, or if the successive body webs are polygonal, the following formula may be formulated:

in which f(R) is a function increasing with R. This funcof which it has been obtained that with uniform web height, the medium gap height decreases with increasing radius and also in axial direction toward the side of the pen while the capillarity increases.

The fountain pen according to the present invention operates as follows. In view of the wetting. contact of the ink thread with the paper to written upon at the tip 24 of the pen, the ink is drawn out of the ink gap 22. This ink gap is fed by the feeding capillaries 21 in pen 20. The feeding capillaries 21 withdraw ink from the wedge-shaped gap 52 of the ink conductor 50 which communicates with all winding layers of the helical body 30. Any air which may be present, can escape through the window 43 of the tubular body 40 as well as through the pen cutouts 25 into the peripheral cylinder-shaped air passage between tube- 1 and the helical body. The peripheral air passage is through air slots 53 of the ink conductor 50 and the pertaining window 43 connected to the outside air.

For the sake of completeness, it may also be mentioned that the capillary ink storage means according to the invention is adapted to be fed and post-filled throughthe tubular body 40 from the front side as well as from the rear side. Depending on the position of the designed that in addition to the ink outlet opening a second opening will be made for instance in the cartridge bottom through which air can enter the cartridge. The supply of ink to the capillary body will in all instances occur through the window openings 43 of the wound tubular body 40 adjacent to which as indicated in FIG. 1 a closure body may be provided which prevents a straight passage through pipe 40.

It is, of course, to be understood that the present invention is, by no means, limited to the particular showing in the drawing but also comprises any modifications within the scope of the appended claims.

What is claimed is:

1. In a fountain pen, a tubular housing having a pen at one end, and ink storage means in said housing in communication with said pen, said ink storage means comprising a spirally coiled strip forming a storage body, said strip being formed with protuberant webs whereby adjacent convolutions of the storage body formed by said strips are radially spaced from each other for flatter through-passages, said storage body thereby increasing in capillarity in the axial and radial directions toward said pen, said webs extending from edge to edge of said strip and being inclined to the direction of the length of said strip and having a greater pitch near the axis of said storage body than near the periphery thereof, the ratio of the spacing between adjacent webs in longitudinal direction of the web to the height of the web at the side of the web adjacent to rear end of-the storage body being from about 5 to 1 to about 8 to l and at the opposite side of the web ad jacent to the pen being about 8 to 1 to about 18 to l.

2. A fountain pen according to claim 1 in which the radial spacing between adjacent convolutions of said storage body increases in the radially outward direction thereof.

3. A fountain pen according to claim 2 in which the distance between said web is formulated as d= V K R f (R) wherein .R represents variable radius and K factors are constants such that the webs of adjacent convolutions are circumferentially offset from each other.

4. A fountain pen according to claim 1 in which said webs are from about 10 to microns in height.

5. A fountain pen according to claim 1 in which said webs are from about 20 to 40 microns in height.

6. A fountain pen according to claim 1 in which said webs are formed by residual portions of a photosensitive lacquer deposited on said strip. I

7. A fountain pen according to claim 1 in which said webs are polygonal and having distance between said webs formulated as d=*RXK +f (R).

8. A fountain pen according to claim 1 in which the end faces of said storage body are connected to atmosphere.

9. A fountain pen according to claim 1 in which at least one of the axial and peripheral portions of said storage body is connected to atmosphere.

10. A fountain pen according to claim 1 in which at least the pen end of said storage body is formed as a frustoconical recess.

11. A fountain pen according to claim 1 which includes a tubular core member on which said storage body is mounted.

12. A fountain pen according to claim 1 which includes a tubular core member extending axially through said storage body and having radial apertures at the level of at least one end of said storage body.

13. A fountain pen according to claim 12 in which ink is adapted to be supplied to said storage body via at least one open end of said core member.

14. A fountain pen according to claim 12 in which one end of said tubular core member is in the form of an ink cartridge piercing point.

15. A fountain pen according to claim 1 which includes a tubular core member extending axially through said storage body and having radial apertures at the level of at least one .end of said storage body, said tubular core member having axial ridges protuberant therefrom axially outwardly from said storage body and serving as locating elements.

16. A fountain pen according to claim 1 which includes an ink conducting body abutting at least the pen end of said storage body and provided with at least one capillary passage interconnecting the spaces between all convolutions of said storage body with said pen and also being provided with passages to the atmosphere.

17. A fountain pen according to claim 16 in which said capillary passage is wedge shaped and increases in capillarity toward said pen.

18. A fountain pen according to claim 1 which includes an ink conductor body at each end of said storage body, and resilient means clamping said ink conductor bodies against the ends of said storage body.

19. A fountain pen according to claim 18 in which said resilient means comprises resilient foam washers.

20. A fountain pen according to claim 1 which includes an ink conducting body abutting said storage body on the pen end thereof, said ink conducting body engaging the inside surface of said pen and locating said pen relative to the ink conducting body.

21. A fountain pen according to claim 1 in which each said web is in the form of a series of elongated protuberance arranged in axial alignment in spaced relation.

22. A fountain pen according to claim 21 in which the gaps between adjacent protuberances in each web are staggered from those in the adjacent webs. 

1. In a fountain pen, a tubular housing having a pen at one end, and ink storage means in said housing in communication with said pen, said ink storage means comprising a spirally coiled strip forming a storage body, said strip being formed with protuberant webs whereby adjacent convolutions of the storage body formed by said strips are radially spaced from each other for flatter through-passages, said storage body thereby increasing in capillarity in the axial and radial directions toward said pen, said webs extending from edge to edge of said strip and being inclined to the direction of the length of said strip and having a greater pitch near the axis of said storage body than near the periphery thereof, the ratio of the spacing between adjacent webs in longitudinal direction of the web to the height of the web at the side of the web adjacent to rear end of the storage body being from about 5 to 1 to about 8 to 1 and at the opposite side of the web adjacent to the pen being about 8 to 1 to about 18 to
 1. 2. A fountain pen according to claim 1 in which the radial spacing between adjacent convolutions of said storage body increases in the radially outward direction thereof.
 3. A fountain pen according to claim 2 in which the distance between said web is formulated as d Square Root K1R + f1 (R) wherein R represents variable radius and K factors are constants such that the webs of adjacent convolutions are circumferentially offset from each other.
 4. A fountain pen according to claim 1 in which said webs are from about 10 to 100 microns in height.
 5. A fountain pen according to claim 1 in which said webs are from about 20 to 40 microns in height.
 6. A fountain pen according to claim 1 in which said webs are formed by residual portions of a photosensitive lacquer deposited on said strip.
 7. A fountain pen according to claim 1 in which said webs are polygonal and having distance between said webs formulated as d R X K2 + f2 (R).
 8. A fountain pen according to claim 1 in which the end faces of said storage body are Connected to atmosphere.
 9. A fountain pen according to claim 1 in which at least one of the axial and peripheral portions of said storage body is connected to atmosphere.
 10. A fountain pen according to claim 1 in which at least the pen end of said storage body is formed as a frustoconical recess.
 11. A fountain pen according to claim 1 which includes a tubular core member on which said storage body is mounted.
 12. A fountain pen according to claim 1 which includes a tubular core member extending axially through said storage body and having radial apertures at the level of at least one end of said storage body.
 13. A fountain pen according to claim 12 in which ink is adapted to be supplied to said storage body via at least one open end of said core member.
 14. A fountain pen according to claim 12 in which one end of said tubular core member is in the form of an ink cartridge piercing point.
 15. A fountain pen according to claim 1 which includes a tubular core member extending axially through said storage body and having radial apertures at the level of at least one end of said storage body, said tubular core member having axial ridges protuberant therefrom axially outwardly from said storage body and serving as locating elements.
 16. A fountain pen according to claim 1 which includes an ink conducting body abutting at least the pen end of said storage body and provided with at least one capillary passage interconnecting the spaces between all convolutions of said storage body with said pen and also being provided with passages to the atmosphere.
 17. A fountain pen according to claim 16 in which said capillary passage is wedge shaped and increases in capillarity toward said pen.
 18. A fountain pen according to claim 1 which includes an ink conductor body at each end of said storage body, and resilient means clamping said ink conductor bodies against the ends of said storage body.
 19. A fountain pen according to claim 18 in which said resilient means comprises resilient foam washers.
 20. A fountain pen according to claim 1 which includes an ink conducting body abutting said storage body on the pen end thereof, said ink conducting body engaging the inside surface of said pen and locating said pen relative to the ink conducting body.
 21. A fountain pen according to claim 1 in which each said web is in the form of a series of elongated protuberance arranged in axial alignment in spaced relation.
 22. A fountain pen according to claim 21 in which the gaps between adjacent protuberances in each web are staggered from those in the adjacent webs. 